Biologist awarded nearly $1.5 million for research on water fleas and flies

Biologist awarded nearly $1.5 million for research on water fleas and flies.

By:Kevin Fryling, News and Media Specialist, IU Bloomington

Friday, August 30, 2019

Andy Zelhof.Photo by Terri Greene

Two NSF grants to Andrew Zelhof will support the use of arthropods to advance research on basic biological mechanisms, including vision.

A total of $1.47 million from the National Science Foundation has been awarded to Indiana University to advance research aimed at improving scientists' ability to understand basic biological mechanisms in humans—as well as other species—using arthropods.

The support comes from two grants. The first is $750,000 to study the cellular and molecular mechanisms behind the evolution of insect eyes—such as a fused array of light-catching photoreceptors, as seen in flour beetles, or Tribolium, or an open array of photoreceptors, as seen in the eyes of fruit flies, or Drosophila. The second is $720,000 to transform Daphnia pulex, or "water fleas"—a common micro-crustacean—into a model species for studying how genes interact with their environment.

The primary investigator on the first award is Andrew Zelhof, an associate professor in the IU Bloomington College of Arts and Sciences' Department of Biology and director of the Drosophila Genomics Resource Center at IU. Zelhof is also co-investigator on the second award, whose primary investigator is Michael Lynch, a professor at Arizona State University and former member of the IU faculty. The $720,000 to IU is 40 percent of the second grant's $1.8 million total.

"These awards are related in their use of model species to illuminate the big questions in basic biology," Zelhof said. "In creating new genetic tools for Daphnia, we aim to bridge a gap between molecular and cellular genetics and understanding the emergence of new physical traits in response to their environment. In studying insect eyes, we're seeking to address a key question in evolutionary and developmental biology, which is how evolutionarily conserved cellular processes are modified to produce adaptive changes despite the constraints required to construct functional tissue."

Drosophila eye. One of the grants will support research on light-sensing organs in various arthropods, including Drosophila.

The term "conserved" refers to biological mechanisms whose essential function has remained unchanged over time despite the growing complexity of the surrounding organism. For example, approximately 70 percent of human genes associated with diseases are also found in fruit flies. Arthropods, which include crustaceans and insects, are powerful model species for studying basic genetic mechanisms due to the existence of these processes.

Moreover, IU is well positioned to advance research on the use of these organisms in science as the site of three world-class facilities in fruit fly genetics: The Bloomington Drosophila Stock Center, which maintains over 71,000 genetically different fruit fly strains for shipment to research labs across the globe; the Drosophila Genomics Resource Center, which develops and tests new technologies for studying genetics in fruit flies; and FlyBase, the most comprehensive database of fruit fly DNA sequence information in the world.

Daphnia hold strong research potential due to a number of unique qualities, Zelhof said, including the short amount of time between their generation cycles; their easily observable, transparent bodies; and the low-cost of storing their eggs over decades. Specifically, he said the Daphnia grant will support the creation of new water fleas with genetic modifications that let scientists easily insert new or modified gene sequences into their DNA.

In addition, the award will support the establishment of a Daphnia resource center, similar to the Drosophila Genomics Resource Center, for storing and distributing these new genetic tools to researchers across the globe. Also planned are workshops to educate researchers in the use of this new "molecular toolbox," which will allow biologists with little gene editing experience to easily investigate the molecular, cellular, developmental and behavioral role of any gene in Daphnia.

One of the grants will support research to transform water fleas into a model species to study how new physical traits emerge through interaction with the environment.

Similarly, the eye grant is designed to reveal the essential "blueprints" behind the design and function of animal eyes. By studying the structural organization of different light-sensing organs in various arthropods, Zelhof said, researchers will discover "fundamental design principles" that can inform the development of artificial systems for light detection and vision, as well as "information that promotes a deeper understanding of our own human eyes."

"Under the support from NSF, we expect Daphnia pulex to become established rapidly as a major model for the integrative understanding of organismal biology," Zelhof added. "We're also eager for the new insights on vision to emerge from our other funded project."